What type of platform are you most comfortable supporting - Unix,
Windows, Linux?

How will the data for the large tables arrive? A flat (ASCII) file?

What is the time frame between the arrival of the data and the time the
data must be ready for users?

Have you licensed Oracle yet? What type of license?

Will the large monthly data loads be kept for several months? If so,
consider licensing Oracle partitioning.

How tight is your budget? Is your organization willing to pay a
reasonable amount, or are you trying to get by paying very little money and
are willing to spend more of your time keeping this application running?

What type of data access is needed (via Java)? How many users? What type
of queries -- simple lookups of data or will the queries be sophisticated?